net/mlx4_en: Add HW timestamping (TS) support

The patch allows to enable/disable HW timestamping for incoming and/or
outgoing packets. It adds and initializes all structs and callbacks
needed by kernel TS API.
To enable/disable HW timestamping appropriate ioctl should be used.
Currently HWTSTAMP_FILTER_ALL/NONE and HWTSAMP_TX_ON/OFF only are
supported.
When enabling TS on receive flow - VLAN stripping will be disabled.
Also were made all relevant changes in RX/TX flows to consider TS request
and plant HW timestamps into relevant structures.
mlx4_ib was fixed to compile with new mlx4_cq_alloc() signature.

Signed-off-by: Eugenia Emantayev <[email protected]>
Signed-off-by: Amir Vadai <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: amirv

drivers/infiniband/hw/mlx4/cq.c

@@ -228,7 +228,7 @@ struct ib_cq *mlx4_ib_create_cq(struct ib_device *ibdev, int entries, int vector
 		vector = dev->eq_table[vector % ibdev->num_comp_vectors];
 
 	err = mlx4_cq_alloc(dev->dev, entries, &cq->buf.mtt, uar,
-			    cq->db.dma, &cq->mcq, vector, 0);
+			    cq->db.dma, &cq->mcq, vector, 0, 0);
 	if (err)
 		goto err_dbmap;
 

drivers/net/ethernet/mellanox/mlx4/Makefile

@@ -6,5 +6,5 @@ mlx4_core-y :=	alloc.o catas.o cmd.o cq.o eq.o fw.o icm.o intf.o main.o mcg.o \
 obj-$(CONFIG_MLX4_EN)               += mlx4_en.o
 
 mlx4_en-y := 	en_main.o en_tx.o en_rx.o en_ethtool.o en_port.o en_cq.o \
-		en_resources.o en_netdev.o en_selftest.o
+		en_resources.o en_netdev.o en_selftest.o en_clock.o
 mlx4_en-$(CONFIG_MLX4_EN_DCB) += en_dcb_nl.o

drivers/net/ethernet/mellanox/mlx4/cq.c

@@ -240,9 +240,10 @@ static void mlx4_cq_free_icm(struct mlx4_dev *dev, int cqn)
 		__mlx4_cq_free_icm(dev, cqn);
 }
 
-int mlx4_cq_alloc(struct mlx4_dev *dev, int nent, struct mlx4_mtt *mtt,
-		  struct mlx4_uar *uar, u64 db_rec, struct mlx4_cq *cq,
-		  unsigned vector, int collapsed)
+int mlx4_cq_alloc(struct mlx4_dev *dev, int nent,
+		  struct mlx4_mtt *mtt, struct mlx4_uar *uar, u64 db_rec,
+		  struct mlx4_cq *cq, unsigned vector, int collapsed,
+		  int timestamp_en)
 {
 	struct mlx4_priv *priv = mlx4_priv(dev);
 	struct mlx4_cq_table *cq_table = &priv->cq_table;
@@ -276,6 +277,9 @@ int mlx4_cq_alloc(struct mlx4_dev *dev, int nent, struct mlx4_mtt *mtt,
 	memset(cq_context, 0, sizeof *cq_context);
 
 	cq_context->flags	    = cpu_to_be32(!!collapsed << 18);
+	if (timestamp_en)
+		cq_context->flags  |= cpu_to_be32(1 << 19);
+
 	cq_context->logsize_usrpage = cpu_to_be32((ilog2(nent) << 24) | uar->index);
 	cq_context->comp_eqn	    = priv->eq_table.eq[vector].eqn;
 	cq_context->log_page_size   = mtt->page_shift - MLX4_ICM_PAGE_SHIFT;

drivers/net/ethernet/mellanox/mlx4/en_clock.c

@@ -0,0 +1,132 @@
+/*
+ * Copyright (c) 2012 Mellanox Technologies. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ */
+
+#include <linux/mlx4/device.h>
+
+#include "mlx4_en.h"
+
+int mlx4_en_timestamp_config(struct net_device *dev, int tx_type, int rx_filter)
+{
+	struct mlx4_en_priv *priv = netdev_priv(dev);
+	struct mlx4_en_dev *mdev = priv->mdev;
+	int port_up = 0;
+	int err = 0;
+
+	mutex_lock(&mdev->state_lock);
+	if (priv->port_up) {
+		port_up = 1;
+		mlx4_en_stop_port(dev, 1);
+	}
+
+	mlx4_en_free_resources(priv);
+
+	en_warn(priv, "Changing Time Stamp configuration\n");
+
+	priv->hwtstamp_config.tx_type = tx_type;
+	priv->hwtstamp_config.rx_filter = rx_filter;
+
+	if (rx_filter != HWTSTAMP_FILTER_NONE)
+		dev->features &= ~NETIF_F_HW_VLAN_CTAG_RX;
+	else
+		dev->features |= NETIF_F_HW_VLAN_CTAG_RX;
+
+	err = mlx4_en_alloc_resources(priv);
+	if (err) {
+		en_err(priv, "Failed reallocating port resources\n");
+		goto out;
+	}
+	if (port_up) {
+		err = mlx4_en_start_port(dev);
+		if (err)
+			en_err(priv, "Failed starting port\n");
+	}
+
+out:
+	mutex_unlock(&mdev->state_lock);
+	netdev_features_change(dev);
+	return err;
+}
+
+/* mlx4_en_read_clock - read raw cycle counter (to be used by time counter)
+ */
+static cycle_t mlx4_en_read_clock(const struct cyclecounter *tc)
+{
+	struct mlx4_en_dev *mdev =
+		container_of(tc, struct mlx4_en_dev, cycles);
+	struct mlx4_dev *dev = mdev->dev;
+
+	return mlx4_read_clock(dev) & tc->mask;
+}
+
+u64 mlx4_en_get_cqe_ts(struct mlx4_cqe *cqe)
+{
+	u64 hi, lo;
+	struct mlx4_ts_cqe *ts_cqe = (struct mlx4_ts_cqe *)cqe;
+
+	lo = (u64)be16_to_cpu(ts_cqe->timestamp_lo);
+	hi = ((u64)be32_to_cpu(ts_cqe->timestamp_hi) + !lo) << 16;
+
+	return hi | lo;
+}
+
+void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev,
+			    struct skb_shared_hwtstamps *hwts,
+			    u64 timestamp)
+{
+	u64 nsec;
+
+	nsec = timecounter_cyc2time(&mdev->clock, timestamp);
+
+	memset(hwts, 0, sizeof(struct skb_shared_hwtstamps));
+	hwts->hwtstamp = ns_to_ktime(nsec);
+}
+
+void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev)
+{
+	struct mlx4_dev *dev = mdev->dev;
+
+	memset(&mdev->cycles, 0, sizeof(mdev->cycles));
+	mdev->cycles.read = mlx4_en_read_clock;
+	mdev->cycles.mask = CLOCKSOURCE_MASK(48);
+	/* Using shift to make calculation more accurate. Since current HW
+	 * clock frequency is 427 MHz, and cycles are given using a 48 bits
+	 * register, the biggest shift when calculating using u64, is 14
+	 * (max_cycles * multiplier < 2^64)
+	 */
+	mdev->cycles.shift = 14;
+	mdev->cycles.mult =
+		clocksource_khz2mult(1000 * dev->caps.hca_core_clock, mdev->cycles.shift);
+
+	timecounter_init(&mdev->clock, &mdev->cycles,
+			 ktime_to_ns(ktime_get_real()));
+}

drivers/net/ethernet/mellanox/mlx4/en_cq.c

@@ -77,6 +77,7 @@ int mlx4_en_activate_cq(struct mlx4_en_priv *priv, struct mlx4_en_cq *cq,
 	struct mlx4_en_dev *mdev = priv->mdev;
 	int err = 0;
 	char name[25];
+	int timestamp_en = 0;
 	struct cpu_rmap *rmap =
 #ifdef CONFIG_RFS_ACCEL
 		priv->dev->rx_cpu_rmap;
@@ -123,8 +124,13 @@ int mlx4_en_activate_cq(struct mlx4_en_priv *priv, struct mlx4_en_cq *cq,
 	if (!cq->is_tx)
 		cq->size = priv->rx_ring[cq->ring].actual_size;
 
-	err = mlx4_cq_alloc(mdev->dev, cq->size, &cq->wqres.mtt, &mdev->priv_uar,
-			    cq->wqres.db.dma, &cq->mcq, cq->vector, 0);
+	if ((cq->is_tx && priv->hwtstamp_config.tx_type) ||
+	    (!cq->is_tx && priv->hwtstamp_config.rx_filter))
+		timestamp_en = 1;
+
+	err = mlx4_cq_alloc(mdev->dev, cq->size, &cq->wqres.mtt,
+			    &mdev->priv_uar, cq->wqres.db.dma, &cq->mcq,
+			    cq->vector, 0, timestamp_en);
 	if (err)
 		return err;
 

drivers/net/ethernet/mellanox/mlx4/en_ethtool.c

@@ -1147,6 +1147,35 @@ static int mlx4_en_set_channels(struct net_device *dev,
 	return err;
 }
 
+static int mlx4_en_get_ts_info(struct net_device *dev,
+			       struct ethtool_ts_info *info)
+{
+	struct mlx4_en_priv *priv = netdev_priv(dev);
+	struct mlx4_en_dev *mdev = priv->mdev;
+	int ret;
+
+	ret = ethtool_op_get_ts_info(dev, info);
+	if (ret)
+		return ret;
+
+	if (mdev->dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_TS) {
+		info->so_timestamping |=
+			SOF_TIMESTAMPING_TX_HARDWARE |
+			SOF_TIMESTAMPING_RX_HARDWARE |
+			SOF_TIMESTAMPING_RAW_HARDWARE;
+
+		info->tx_types =
+			(1 << HWTSTAMP_TX_OFF) |
+			(1 << HWTSTAMP_TX_ON);
+
+		info->rx_filters =
+			(1 << HWTSTAMP_FILTER_NONE) |
+			(1 << HWTSTAMP_FILTER_ALL);
+	}
+
+	return ret;
+}
+
 const struct ethtool_ops mlx4_en_ethtool_ops = {
 	.get_drvinfo = mlx4_en_get_drvinfo,
 	.get_settings = mlx4_en_get_settings,
@@ -1173,6 +1202,7 @@ const struct ethtool_ops mlx4_en_ethtool_ops = {
 	.set_rxfh_indir = mlx4_en_set_rxfh_indir,
 	.get_channels = mlx4_en_get_channels,
 	.set_channels = mlx4_en_set_channels,
+	.get_ts_info = mlx4_en_get_ts_info,
 };
 
 

drivers/net/ethernet/mellanox/mlx4/en_main.c

@@ -300,6 +300,11 @@ static void *mlx4_en_add(struct mlx4_dev *dev)
 		if (mlx4_en_init_netdev(mdev, i, &mdev->profile.prof[i]))
 			mdev->pndev[i] = NULL;
 	}
+
+	/* Initialize time stamp mechanism */
+	if (mdev->dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_TS)
+		mlx4_en_init_timestamp(mdev);
+
 	return mdev;
 
 err_mr:

drivers/net/ethernet/mellanox/mlx4/en_netdev.c

@@ -1916,6 +1916,75 @@ static int mlx4_en_change_mtu(struct net_device *dev, int new_mtu)
 	return 0;
 }
 
+static int mlx4_en_hwtstamp_ioctl(struct net_device *dev, struct ifreq *ifr)
+{
+	struct mlx4_en_priv *priv = netdev_priv(dev);
+	struct mlx4_en_dev *mdev = priv->mdev;
+	struct hwtstamp_config config;
+
+	if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
+		return -EFAULT;
+
+	/* reserved for future extensions */
+	if (config.flags)
+		return -EINVAL;
+
+	/* device doesn't support time stamping */
+	if (!(mdev->dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_TS))
+		return -EINVAL;
+
+	/* TX HW timestamp */
+	switch (config.tx_type) {
+	case HWTSTAMP_TX_OFF:
+	case HWTSTAMP_TX_ON:
+		break;
+	default:
+		return -ERANGE;
+	}
+
+	/* RX HW timestamp */
+	switch (config.rx_filter) {
+	case HWTSTAMP_FILTER_NONE:
+		break;
+	case HWTSTAMP_FILTER_ALL:
+	case HWTSTAMP_FILTER_SOME:
+	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
+	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
+	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
+	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
+	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
+	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
+	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
+	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
+	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
+	case HWTSTAMP_FILTER_PTP_V2_EVENT:
+	case HWTSTAMP_FILTER_PTP_V2_SYNC:
+	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
+		config.rx_filter = HWTSTAMP_FILTER_ALL;
+		break;
+	default:
+		return -ERANGE;
+	}
+
+	if (mlx4_en_timestamp_config(dev, config.tx_type, config.rx_filter)) {
+		config.tx_type = HWTSTAMP_TX_OFF;
+		config.rx_filter = HWTSTAMP_FILTER_NONE;
+	}
+
+	return copy_to_user(ifr->ifr_data, &config,
+			    sizeof(config)) ? -EFAULT : 0;
+}
+
+static int mlx4_en_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+	switch (cmd) {
+	case SIOCSHWTSTAMP:
+		return mlx4_en_hwtstamp_ioctl(dev, ifr);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
 static int mlx4_en_set_features(struct net_device *netdev,
 		netdev_features_t features)
 {
@@ -1943,6 +2012,7 @@ static const struct net_device_ops mlx4_netdev_ops = {
 	.ndo_set_mac_address	= mlx4_en_set_mac,
 	.ndo_validate_addr	= eth_validate_addr,
 	.ndo_change_mtu		= mlx4_en_change_mtu,
+	.ndo_do_ioctl		= mlx4_en_ioctl,
 	.ndo_tx_timeout		= mlx4_en_tx_timeout,
 	.ndo_vlan_rx_add_vid	= mlx4_en_vlan_rx_add_vid,
 	.ndo_vlan_rx_kill_vid	= mlx4_en_vlan_rx_kill_vid,
@@ -2054,6 +2124,11 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int port,
 	spin_lock_init(&priv->filters_lock);
 #endif
 
+	/* Initialize time stamping config */
+	priv->hwtstamp_config.flags = 0;
+	priv->hwtstamp_config.tx_type = HWTSTAMP_TX_OFF;
+	priv->hwtstamp_config.rx_filter = HWTSTAMP_FILTER_NONE;
+
 	/* Allocate page for receive rings */
 	err = mlx4_alloc_hwq_res(mdev->dev, &priv->res,
 				MLX4_EN_PAGE_SIZE, MLX4_EN_PAGE_SIZE);

drivers/net/ethernet/mellanox/mlx4/en_resources.c

@@ -42,6 +42,7 @@ void mlx4_en_fill_qp_context(struct mlx4_en_priv *priv, int size, int stride,
 			     int user_prio, struct mlx4_qp_context *context)
 {
 	struct mlx4_en_dev *mdev = priv->mdev;
+	struct net_device *dev = priv->dev;
 
 	memset(context, 0, sizeof *context);
 	context->flags = cpu_to_be32(7 << 16 | rss << MLX4_RSS_QPC_FLAG_OFFSET);
@@ -65,6 +66,8 @@ void mlx4_en_fill_qp_context(struct mlx4_en_priv *priv, int size, int stride,
 	context->cqn_send = cpu_to_be32(cqn);
 	context->cqn_recv = cpu_to_be32(cqn);
 	context->db_rec_addr = cpu_to_be64(priv->res.db.dma << 2);
+	if (!(dev->features & NETIF_F_HW_VLAN_CTAG_RX))
+		context->param3 |= cpu_to_be32(1 << 30);
 }